ResponseContainerTemplateFilter.java

package org.jboss.resteasy.test.providers.custom.resource;


import org.jboss.logging.Logger;

import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.Response;
import java.io.IOException;
import java.lang.reflect.Method;

public abstract class ResponseContainerTemplateFilter implements ContainerResponseFilter {

    public static final String OPERATION = "OPERATION";
    private static Logger logger = Logger.getLogger(ResponseContainerTemplateFilter.class);

    protected ContainerRequestContext requestContext;
    protected ContainerResponseContext responseContext;

    @Override
    public void filter(ContainerRequestContext requestContext,
                       ContainerResponseContext responseContext) throws IOException {
        this.requestContext = requestContext;
        this.responseContext = responseContext;
        String operation = getHeaderString();
        Method[] methods = getClass().getMethods();
        for (Method method : methods) {
            if (operation != null) {
                if (operation.equalsIgnoreCase(method.getName())) {
                    try {
                        method.invoke(this);
                        return;
                    } catch (Exception e) {
                        logger.error("The requested resource is not available", e);
                        responseContext.setStatus(Response.Status.SERVICE_UNAVAILABLE
                                .getStatusCode());
                        setEntity(e.getMessage());
                        return;
                    }
                }
            }
        }
        operationMethodNotFound(operation);
    }

    protected void operationMethodNotFound(String operation) {
        responseContext.setStatus(Response.Status.SERVICE_UNAVAILABLE.getStatusCode());
        setEntity("Operation " + operation + " not implemented");
    }

    // ///////////////////////////////////////////////////////////////////
    protected boolean assertTrue(boolean conditionTrue, Object... msg) {
        if (conditionTrue) {
            return false;
        }
        StringBuilder sb = new StringBuilder();
        if (msg != null) {
            for (Object str : msg) {
                sb.append(str).append(" ");
            }
        }
        setEntity(sb.toString());
        responseContext.setStatus(Response.Status.NOT_ACCEPTABLE.getStatusCode());
        return true;
    }

    protected String getHeaderString() {
        MultivaluedMap<String, Object> headers = responseContext.getHeaders();
        return (String) headers.getFirst(OPERATION);
    }

    protected void setEntity(String entity) {
        responseContext.setEntity(entity, null, MediaType.TEXT_PLAIN_TYPE);
    }

}